ecoflex comparative lcaecoflexsoutheastnsw.com.au/casestudies/lca-carbon... · ecoflex –...

Ecoflex – Comparative Partial LCA 19 December 2012

of 44 Sustainable Business Consulting

Extended Gate-to-GateComparative LCA

for Access Road PavementIn association with Sustainability Advantage

EcoflexE-Pave

vsAggregate-O

nly Pavement

Sustainable Business Consulting Pty Ltd | Level 32, 101 Miller Street, North Sydney 2060P: 1300 102 195 | F: +61 2 8079 6101 | www.sustainablebizconsulting.com.au

ACN 140 233 932 | ABN 46 506 219 241



Table of Contents

TABLE OF CONTENTS........................................................................................................................................2

TABLE OF FIGURES ...........................................................................................................................................3

1. EXECUTIVE SUMMARY.............................................................................................................................5

2. ORGANISATION DESCRIPTION .................................................................................................................6

3. CARBON LCA BACKGROUND AND METHODOLOGY .................................................................................6

3.1. LCA BOUNDARY – BACKGROUND.................................................................................................................. 73.2. LCA BUSINESS GOALS FOR ECOFLEX .............................................................................................................. 8

4. LCA DATASET USAGE GUIDELINES ...........................................................................................................9

5. LCA METHODOLOGY..............................................................................................................................10

6. SCOPE AND SYSTEM BOUNDARY ...........................................................................................................11

6.1. SCOPE OF STUDY...................................................................................................................................... 116.2. SYSTEM BOUNDARY.................................................................................................................................. 12

7. FUNCTIONAL UNIT.................................................................................................................................13

8. THE E-PAVE PROCESS LIFE CYCLE INVENTORY........................................................................................15

8.1. PROCESS DESCRIPTION - E-PAVE ................................................................................................................. 158.2. DATA COLLECTION - E-PAVE PROCESS.......................................................................................................... 168.3. EMISSION CALCULATIONS, EMISSION FACTORS AND METHODOLOGIES - E-PAVE PROCESS ..................................... 178.4. ASSUMPTIONS / LIMITATIONS - E-PAVE PROCESS........................................................................................... 208.5. EMISSION EXCLUSIONS FROM WITHIN THE SYSTEM BOUNDARY - E-PAVE PROCESS............................................... 218.6. EMISSIONS PER FUNCTIONAL UNIT – E-PAVE PROCESS .................................................................................... 228.7. ASSESSMENT OF UNCERTAINTY - E-PAVE ...................................................................................................... 22

9. THE ‘AGGREGATE-ONLY’ PROCESS LIFE CYCLE INVENTORY....................................................................23

9.1. PROCESS DESCRIPTION – AGGREGATE-ONLY ................................................................................................. 239.2. DATA COLLECTION - AGGREGATE-ONLY PROCESS........................................................................................... 239.3. EMISSION CALCULATIONS, EMISSION FACTORS AND METHODOLOGIES – AGGREGATE-ONLY PROCESS...................... 249.4. ASSUMPTIONS / LIMITATIONS - AGGREGATE-ONLY PROCESS ............................................................................ 279.5. EMISSION EXCLUSIONS FROM WITHIN THE SYSTEM BOUNDARY – AGGREGATE-ONLY PROCESS ............................... 289.6. EMISSIONS PER FUNCTIONAL UNIT - AGGREGATE-ONLY PROCESS...................................................................... 299.7. ASSESSMENT OF UNCERTAINTY - AGGREGATE-ONLY PROCESS .......................................................................... 29

10. IMPACT ASSESSMENT........................................................................................................................30

11. COMPARING THE CARBON FOOTPRINT OF E-PAVE AGAINST THE AGGREGATE-ONLY PROCESS ........31

12. CONCLUSION AND IMPLICATIONS.....................................................................................................34

13. RECOMMENDATIONS FOR FUTURE IMPROVEMENT OF THIS LCA STUDY ..........................................36

14. APPENDIX A: ADDITIONAL CONSIDERATIONS - RISING INPUT COSTS AND CARBON PRICING............37



15. APPENDIX B – DATA SET E-PAVE PROCESS LIFECYCLE INVENTORY...................................................38

16. APPENDIX C – DATA SET AGGREGATE-ONLY PROCESS LIFECYCLE INVENTORY .................................39

17. APPENDIX D – DATA SET SUBSTANTIATION REFERENCES ..................................................................40

Cover photo of ‘Road on a floodplain on the southern side of South West Rocks’, courtesy Ecoflex P/L

Table of Figures

FIGURE 1: CARBON LCA ............................................................................................................................................... 6FIGURE 2: CRADLE-TO-GRAVE VERSUS GATE-TO-GATE LCA ................................................................................................ 7FIGURE 3: PHASES OF AN LCA - ISO 14040 & 14044 (2006) ......................................................................................... 10FIGURE 4: SCOPE OF STUDY - COMPARING THE TWO DIFFERENT PRODUCT CARBON FOOTPRINTS ............................................. 11FIGURE 5: LCA PROCESS BOUNDARY - OVERVIEW ........................................................................................................... 12FIGURE 6: LCA PROCESS DIAGRAM AND BOUNDARY FOR AGGREGATE-ONLY AND E-PAVE METHODS........................................ 14FIGURE 7: THE ECOFLEX E-PAVE T-UNIT........................................................................................................................ 15FIGURE 8: FORMULA FOR CALCULATING FUEL-ASSOCIATED EMISSIONS................................................................................ 17FIGURE 9: EMISSIONS BREAKDOWN BY ACTIVITY - E-PAVE PROCESS.................................................................................... 19FIGURE 10: FORMULA FOR CALCULATING FUEL-ASSOCIATED EMISSIONS.............................................................................. 24FIGURE 11: EMISSIONS BREAKDOWN BY ACTIVITY – AGGREGATE-ONLY PROCESS .................................................................. 26FIGURE 12: DIESEL CONSUMPTION IN LITRES AGGREGATE-ONLY VERSUS E-PAVE.................................................................. 31FIGURE 13: PETROL CONSUMPTION IN LITRES AGGREGATE-ONLY VERSUS E-PAVE ................................................................ 31FIGURE 14: CARBON EMISSIONS AGGREGATE-ONLY VERSUS E-PAVE .................................................................................. 32FIGURE 15: CARBON EMISSIONS– PIE CHART ................................................................................................................. 32FIGURE 16: E-PAVE VERSUS AGGREGATE-ONLY; DIESEL, PETROL AND CARBON EMISSIONS IN PERCENTAGES.............................. 32FIGURE 17: COMPARATIVE CARBON FOOTPRINT MAKEUP - E-PAVE AND AGGREGATE-ONLY METHODS .................................... 33FIGURE 18: COMPARATIVE FUEL CONSUMPTION AND CARBON EMISSIONS PERFORMANCE E-PAVE AND AGGREGATE-ONLY .......... 34FIGURE 19: CARBON EMISSIONS IN TONNES; AGGREGATE-ONLY VERSUS E-PAVE PROCESS – BAR CHART.................................. 35FIGURE 20: DATA SET AGGREGATE-ONLY PROCESS LIFECYCLE INVENTORY ........................................................................... 39FIGURE 21: DATA SUBSTANTIATION ENGINEER SPECIFICATION – LETTER .............................................................................. 41FIGURE 22: DATA SUBSTANTIATION ENGINEER SPECIFICATION - CALCULATIONS .................................................................... 42FIGURE 23: DATA SUBSTANTIATION ENGINEER SPECIFICATION - DRAWINGS ......................................................................... 43



Table of TablesTABLE 1: DATASET USAGE GUIDELINES ............................................................................................................................ 9TABLE 2: LIFE CYCLE INVENTORY FOR THE E-PAVE PROCESS ............................................................................................... 18TABLE 3: ASSUMPTIONS / LIMITATIONS FOR E-PAVE PROCESS ........................................................................................... 20TABLE 4: EXCLUSIONS FOR E-PAVE PROCESS................................................................................................................... 21TABLE 5: EMISSIONS PER FUNCTIONAL UNIT – E-PAVE PROCESS ........................................................................................ 22TABLE 6: LIFE CYCLE INVENTORY FOR THE AGGREGATE-ONLY PROCESS ................................................................................ 25TABLE 7: ASSUMPTIONS / LIMITATIONS FOR THE AGGREGATE-ONLY PROCESS....................................................................... 27TABLE 8: EXCLUSIONS FOR AGGREGATE-ONLY PROCESS.................................................................................................... 28TABLE 9: EMISSIONS PER FUNCTIONAL UNIT – AGGREGATE-ONLY PROCESS.......................................................................... 29TABLE 10: DATA SET E-PAVE PROCESS LIFECYCLE INVENTORY............................................................................................ 38TABLE 11: DATA SUBSTANTIATION – BOTH PROCESSES..................................................................................................... 40



1. Executive Summary

This report details the methodology and findings of an ‘Extended Gate to Gate’ Process Life CycleAssessment (LCA) on two different pavement methods used for paving an access road:

Ecoflex E-Pave T-units with Aggregate; andAggregate-Only.

The goal of the LCA is to quantify the carbon emissions generated by these two pavement methodsand to communicate credible, independently verified information to inform decisions ofstakeholders, both internally and externally. It concludes that the Aggregate-Only method issignificantly more emissions-intensive than the Ecoflex E-Pave method, primarily due to the amountof aggregate required to achieve the engineer specified 2:1 batter angle.

The processes studied in this ‘Extended Gate to Gate’ LCA include only two components out of theentire life cycle: namely the ‘pavement process’ and ‘raw material delivery transport’ emissions. Thisincludes ground preparation, geotextile laying, pavement laying, pavement capping and edgetreatment, oversight and compaction emissions. The ‘Gate to Gate’ boundary was extended toinclude the transport of raw materials. The functional unit in this study is the application of 5000 m2

(1000 m (L) x 5 m (W)) of pavement (access road) .The data is based on information provided byEcoflex and its suppliers, specifications and qualified estimates. An impact assessment anduncertainty analysis was performed for emissions factors, energy content and activity data.

The outcomes are summarised below:



2. Organisation Description

Ecoflex Australia recycles used tyres into construction material for paving, retaining walls and use inerosion prevention.

3. Carbon LCA Background and Methodology

With the rise in fuel and energy costs and the pricing of carbon, Australian companies areincreasingly becoming aware of the implications of ‘cost pass through’ along the supply chain ofproducts and services. Operating in such a context, it is more and more important for organisationsto understand emission profiles and to use that knowledge as part of their own procurement andemission reduction strategies.

Figure 1: Carbon LCA



A Carbon LCA is a methodology that is designed to help businesses measure and quantify the end-to-end impacts of a product, process, or service on Global Warming. By rigorously examining each stepin the life cycle, LCA takes into account how raw materials were extracted; energy used duringmanufacturing, packaging, and distribution; global warming impacts from using the product; andwaste created throughout the process and at end-of-life (see Figure 1: Carbon LCA).

3.1. LCA Boundary – BackgroundThere are many variations of the ‘cradle to grave’ LCA which includes a full assessment from rawmaterial extraction to disposal after a product’s end use. One variation is the ‘Gate to Gate’ LCA,which is a partial LCA, focussing on one or two processes in the entire life cycle, usually the‘Production’ process (see Figure 2: Cradle-to-Grave versus Gate-to-Gate LCA).

Figure 2: Cradle-to-Grave versus Gate-to-Gate LCA



3.2. LCA Business Goals for EcoflexThe goal of this ‘Extended Gate to Gate’ Process LCA is to quantify, compare and contrast the carbonemissions generated by the raw material delivery transport and the pavement process of twodifferent methods of access road pavements:


This study was commissioned to communicate credible, independently verified information toinform decisions of stakeholders, both internally and externally. Specifically, Ecoflex would like toachieve the following business goals with this LCA:

Increase market opportunities by pursuing greenhouse gas reduction opportunities and costsavings to create a low-emitting product;Strengthen Ecoflex’s brand image regarding the greenhouse gas performance;Strengthen corporate reputation and accountability through public disclosure of carbonfootprint information.



4. LCA Dataset Usage Guidelines

Table 1: Dataset Usage Guidelines

Name of Process Pavement (Access Road)

Functional Unit 5000 m2 (1000m (L) x 5m (W)) with engineer specified 2:1 batter angleApplication Considerations for civil projects which include laying district or access roads

Location Hunter region, NSW, Australia

Use Guidelines forData set

This data has been compiled with the aim of performing a comparativeanalysis of different pavement methods available in the Australian markettoday. The LCA is an ‘Extended Gate to Gate’ Process LCA, focussing on thepavement process and raw material delivery transport emissions, which formpart of the entire life cycle.

Data Source The data was based on information provided by Ecoflex and its suppliers,specifications and qualified estimates.

Emission and EnergyContent FactorSource

National Greenhouse Account (NGA) Factors July 2012

CommissioningOrganisation of dataset

Ecoflex Australia P/L

Contact Person Jim Grant (Ecoflex), ManagerContact Details +61 2 4940 0178

LCA Consultant Sustainable Business ConsultingBarbara Albert, Principal ConsultantGenevieve Lee, Senior Consultant

Standard(s) this LCAhas been preparedin consideration of

National Greenhouse & Energy Reporting SchemeISO 14040:2006ISO 14044:2006PAS 2050GHG Protocol: A Corporate Accounting and Reporting StandardGHG Protocol: Product Life Cycle Accounting and Reporting StandardGHG Protocol: Corporate Value Chain (Scope 3) Accounting andReporting Standard

Date 19 Dec 2012



5. LCA Methodology

The LCA method as described in ISO 14040 and 14044 (2006), has four main phases:

1.) Goal and Scope definition- described in sections 3.2 (LCA Business Goals for Ecoflex) and 6(Scope and System Boundary)

2.) Inventory Analysis of input and output emissions data- described sections 8 and 93.) Impact Assessment- described in section 104.) Interpretation of Results- described in section 11 and 12.

Figure 3: Phases of an LCA - ISO 14040 & 14044 (2006)



6. Scope and System Boundary

6.1. Scope of StudyThis study quantifies and compares the carbon emissions generated by two different methods ofaccess road pavement:


Figure 4: Scope of Study - Comparing the Two Different Product Carbon Footprints

The processes studied in this ‘Extended Gate to Gate’ LCA include only two components out of theentire life cycle: ‘pavement process’ and ‘raw material delivery transport’ emissions. In bothprocesses, the ground is prepared and polypropylene geotextile is delivered and laid.

In the Ecoflex E-Pave process, 5000 recycled tyre E-Pave T-units are delivered and laid and infilledwith delivered aggregate to satisfy the engineer-specified 2:1 batter angle for the pavement.

In the Aggregate-Only process, delivered aggregate is laid to satisfy the engineer specified 2:1 batterangle for the pavement.

Both processes then cap the pavement with aggregate, treat the edges and apply compaction tofinalise the pavement. Supervision occurs daily for both. (Refer to Figure 6: LCA Process Diagram andBoundary for Aggregate-Only and E-Pave Methods)



6.2. System BoundaryCompleting an LCA helps businesses make strategic and tactical sustainability decisions. An LCA canbe complex and time-consuming, and therefore costly. This has deterred many businesses fromundertaking lifecycle assessments. However, an LCA study can also be customised and streamlinedto be a less expensive and rigorous endeavour. This is what Sustainable Business Consulting hasdone in the current study. Instead of focussing on a cradle-to-grave boundary, we are focussing onan Extended Gate-to-Gate study, which will return the desired result, namely the comparing of thecarbon footprint of laying 5000 m2 of access road using E-pave units as opposed to using Aggregate-Only.

The system boundary defines the processes included in the LCA study. This LCA study is an ‘Extended‘Gate to Gate’ Process LCA, focussing only on the ‘pavement process’ and ‘raw material deliverytransport’ emission components in the entire life cycle. As such, the components ‘embodiedemissions in input materials’ (with the exception of upstream fuel emissions), ‘road maintenance’and ‘end of life disposal’ are not considered (see Figure 5: LCA Process Boundary - Overview). To gooutside these boundaries introduces project specific circumstances, which are numerous and varied.Typically these could include permanent, temporary or reused structures; source material eithervirgin or recycled.

Figure 5: LCA Process Boundary - Overview



The processes studied include ground preparation, geotextile laying, pavement laying, pavementcapping and edge treatment, oversight and compaction emissions associated with the process oflaying 5000 m2 of pavement (access road). The boundary was extended to include delivery transportfor resources (human and materials).

Emission sources were petrol and diesel. The extraction, production and transport of petrol anddiesel were also considered in this study (embodied emissions).

Geotextile transport emissions have been excluded as they are insignificant and hard tosubstantiate. Geotextile is delivered to the site not as an exclusive run, but as part of a largeinterstate run to multiple sites which varies greatly depending on the daily delivery list. As geotextileis required to be delivered for each method, it was agreed to exclude geotextile transport emissionsto reduce the uncertainty of the final calculation.

7. Functional Unit

The functional unit quantifies the primary function and provides a reference to which input andoutput data can be related. The results of data collection and emissions calculations for eachemission source will be expressed in terms of the functional unit.

The functional unit in this study is the:

Application of 5000 m2 (1000m (L) x 5m (W)) of pavement (access road) with engineer specified 2:1batter angle.



Figure 6: LCA Process Diagram and Boundary for Aggregate-Only and E-Pave Methods



8. The E-Pave Process Life Cycle Inventory

8.1. Process Description - E-PaveAs part of their civil construction business, Ecoflex Australia P/L develops E-Pave T-units from qualitycontrolled recycled truck tyres. The recycled tyre consists of an approved tyre (solid rubber treadwith even thickness, passes strength and rigidity tests), with the side-wall cut out.

Figure 7: The Ecoflex E-Pave T-Unit

The process to lay 5000 m2 of pavement begins with minimal ground preparation using an excavator.A back-up fuelling vehicle is also employed. The next step involves the delivery and laying ofpolypropylene geotextile. Five thousand E-Pave T-units are then delivered by the Tyre Recycler andlaid five across abutting tightly in a ‘honeycomb’ pattern along the length of the geofabric, whichhelps minimise the gaps between the tyres and maintains the pavement’s structural integrity. Theunits are then infilled with sufficient aggregate, trucked from the quarry, to satisfy the engineerspecified 2:1 batter angle for the pavement. This extends the base on either side by 0.5 m.

The pavement is then capped with more aggregate to interlock the fill material and the edges aretreated manually by labourers. Finally, compaction equipment (roller) is used to finalise thepavement. Supervision occurs daily on site.



The embodied emissions of fuel were considered, and the boundary was extended to includedelivery transport for resources (human and materials). Emission sources were petrol and diesel.

8.2. Data Collection - E-Pave ProcessThe data is based on information provided by Ecoflex and its suppliers, specifications and qualifiedestimates. Ecoflex uses both pavement methods as part of their civil construction business. The datawas based on on Hunter region projects, however duration data was based on Ecoflex’s nationwideproject averages over the past 16 years used by Ecoflex for calculating project quotations forpotential clients.

Actual data for excavator, E-Pave delivery and aggregate delivery was provided through supplierservice reports.

A supplier statement was used to support vehicle carrying capacity data.

Data from specifications was used for roller, site supervision and back-up fuelling utility vehicles.

Duration data estimates are based on Ecoflex’s nationwide project average laying rate over the past16 years (unit per person per hour rate) used for calculating project quotations for potential clients.E-Pave projects are usually done in conjunction with other civil projects thus to find acutal ‘E-Paveonly’ project data was difficult. Job data from two projects was found and substantiated the dataestimates used. In fact, it showed the estimates to be conservative.

Pavement depths and compaction roller running times are as per engineer specifications forCalifornia Bearing Ratio (CBR) of 1.

Factors supplied by Ecoflex, such as scaling factors, were used to allow for ground or site conditionsand were applied equally to calculations of both pavement methods.

Data sources and calculation methodology are detailed in Appendix D.



8.3. Emission Calculations, Emission Factors and Methodologies - E-PaveProcess

Table 2 summarises the E-Pave Process Life Cycle Inventory. Activity data quantifies the fuelconsumption. Energy content and emissions factors and emission calculation methodology weresourced from National Greenhouse Account (NGA) Factors July 2012. For heavy vehicles, the factorsfor Euro i were used for both pavement methods, with the result of a more conservative carbonemissions result. Appendix B sets out the data components (in grey) used in fuel calculations.

The emissions were calculated using the following formula below (source: NGA Factors 2012):

Figure 8: Formula for Calculating Fuel-Associated Emissions

The total petrol consumption was 65 litres.

The total diesel consumption was 10,142 litres.

The column heading “t CO2-e” sets out the emissions quantified from each process and itspercentage in the total inventory.

The total emissions generated by the E-Pave Pavement process was 30 tonnes CO2-e.


Table 2: Life Cycle Inventory for the E-Pave Process

Emission source Source ofactivity data

Methodologyreference

Energycontentfactor

Emission factor Activitydata Unit t

CO2-e

% ofFoot-print

Site Visit Petrol

Daily Site Visits- Engineering / Supervision-

Crew Cab Utility- Holden Rodeo Petrol (Post 2004

Vehicle)

Specification NGERS Method 1 from NGA

Factors 2012, Table 4, p. 17

34.2 GJ/kL 66.92 kg CO2-e/GJ 64.62 L 0.15 0.50 %

Delivery Transport DieselE-PAVE-

E-PAVE Delivery Truck (Euro i 15T GVM Truck)

Supplier statement NGERS Method 1 from NGA


38.6 GJ/kL 69.9 kg CO2-e/GJ 316.25 L 0.85 2.88 %

INFILL

(2:1 Batter angle- engineer specified) Extending base

0.5m on either side - Aggregate Delivery Truck (Euro i)

Service Report &

Tare weights of

trucks statement

NGERS Method 1 from NGA


38.6 GJ/kL 69.9 kg CO2-e/GJ 6,115.43 L 16.5 55.75 %

CAPPING-

Aggregate Delivery Truck (Euro i)

Service Report &

Tare weights of

trucks statement



38.6 GJ/kL 69.9 kg CO2-e/GJ 2,446.17 L 6.60 22.30 %

Preparation and Laying DieselExcavator - Doosan 15 tonne M/C (Euro i) Service Report &

Tare weights of

trucks statement



38.6 GJ/kL 69.9 kg CO2-e/GJ 634.62 L 1.71 5.79 %

Back Up Vehicle (Post 2004 Utility) Specification NGERS Method 1 from NGA


38.6 GJ/kL 69.9 kg CO2-e/GJ 430.77 L 1.16 3.92 %

Pavement Laying Labour Transport-Crew Cab Utility-

Holden Rodeo 3L Turbo Diesel (Post 2004 Vehicle)



38.6 GJ/kL 69.9 kg CO2-e/GJ 80.77 L 0.22 0.74 %

Capping & Edging Labour Transport-Crew Cab Utility-




38.6 GJ/kL 69.9 kg CO2-e/GJ 40.38 L 0.11 0.37 %

Compaction DieselCS563E Vibrating Smooth Drum (Euro i Vehicle- Low

fuel usage)



38.6 GJ/kL 69.9 kg CO2-e/GJ L 0.21 0.71 %




Energycontentfactor


CO2-e

% ofFoot-print

Embodied emissions for fuelsPetrol extraction, production, transport NGERS Method. NGA Factors

2012, Table 39, p. 71

34.2 GJ/kL 5.3 kg CO2-e/GJ 64.62 L 0.01 0.04 %

Diesel extraction, production, transport NGERS Method. NGA Factors

2012, Table 39, p. 71

38.6 GJ/kL 5.3 kg CO2-e/GJ 10,142.39 L 2.07 7.01 %

Total emissions 29.60 100%

Figure 9: Emissions Breakdown by Activity - E-Pave Process



8.4. Assumptions / Limitations - E-Pave ProcessThe following table lists the assumptions and limitations of the E-Pave Process:

Table 3: Assumptions / Limitations for E-Pave Process

Emissions source / activity Assumption / limitation and justification

Site Visit and Preparatory Laying Project Days/Hours calculated based on time required for 3labourers laying at 13 E-pave units/hour/person to completethe 5000 m2

Preparatory Laying Hours calculated assumes concurrent use of vehiclesDelivery Transport Location of Quarry to Site: 25 kmSite Visit and Preparatory Laying Location of Office to Site: 20 kmDelivery Transport-Aggregate Quantities for Infill andCapping

Ecoflex applies a 10% scaling factor in the Infill and CappingCalculation for BOTH processes- to allow for extra aggregatedue to irregular ground contour, natural compaction andbatter angle. This results in a factor of 1.11

Delivery Transport All Heavy Vehicle Trucks are non-articulated and Euro i, tobe conservative.

Site Visit and Preparatory Laying Cab crew utility fuel consumption was estimated usingvehicle specifications. Ecoflex applies an additional 20% toallow for site conditions.

Preparatory Laying Back up vehicle utility fuel consumption was estimatedusing vehicle specification and assuming an average speedof 40kph.

1 Refer Appendix B



8.5. Emission Exclusions from Within the System Boundary - E-PaveProcess

Geotextile transport emissions have been excluded as they are insignificant and hard tosubstantiate. Geotextile is delivered to the site, not as an exclusive run, but as part of a largeinterstate run to multiple sites, which vary greatly depending on their daily delivery list. As geotextileis required to be delivered for each method, it was agreed to exclude geotextile transport emissionsto reduce the uncertainty of the final calculation.

The following table details why some emissions sources were considered, but ultimately excludedfrom the inventory.

Table 4: Exclusions for E-Pave Process

Emissions source Reason for exclusion and overall implications forfootprint

Recycled tyre - embodied emissions Outside system boundary for Gate-to-Gate LCAE-Pave T-Unit production Outside system boundary for Gate-to-Gate LCAExtraction of rocks (aggregate) Outside system boundary for Gate-to-Gate LCACrushing of rocks (aggregate) Outside system boundary for Gate-to-Gate LCARoad maintenance emissions Outside system boundary for Gate-to-Gate LCAEnd-of-life of access road Outside system boundary for Gate-to-Gate LCAGeotextile transport emissions Immaterial and the same amount of carbon emissions

across the two different paving methods.Geotextile embodied emissions Outside system boundary for Gate-to-Gate LCA



8.6. Emissions per Functional Unit – E-Pave ProcessThe following table lists the emissions per the functional unit for the Aggregate-Only process:

Table 5: Emissions per Functional Unit – E-Pave Process

Amount of product produced (in functional units) Emissions per functional unit

5000 m2 (access road) pavement, E-Pave process 30 tonnes CO2-e

8.7. Assessment of Uncertainty - E-PaveThe assessment of uncertainty follows the GHG Protocol for the ‘Measurement and EstimationUncertainty of GHG Emissions’ and includes the statistical uncertainties associated with thefollowing parameters:

1. The energy content factor of the fuel2. The carbon dioxide emission factor of the fuel3. The methane emission factor of the fuel4. The nitrous oxide emission factor of the fuel5. The quantity of fuel combusted

The uncertainties from the energy content factor, the carbon dioxide emission factor, the methaneemission factor and the nitrous oxide emission factor have been taken from the NGER MeasurementDetermination 2008, chapter 8 “Assessment of Uncertainty”.

The uncertainties for the quantity of fuel combusted (+/-5%) have been assessed by Jim Grant,Ecoflex.

Across the direct emissions, the cumulative uncertainty is ‘good’ at +/- 7.5%.



9. The ‘Aggregate-Only’ Process Life Cycle Inventory

9.1. Process Description – Aggregate-OnlyThe process to lay 5000 m2 of pavement begins with minimal ground preparation using an excavator.A back-up fuelling vehicle is also employed. The next step involves the delivery and laying ofpolypropylene geotextile. Sufficient aggregate delivered from the quarry to satisfy the engineerspecified 2:1 batter angle for the pavement is laid. This extends the base on either side by 2 metres.

The pavement is then capped with more aggregate to interlock the fill material and the edges aretreated manually by labourers. Finally, compaction equipment (roller) is used to finalise thepavement. Supervision occurs daily on site.

The embodied emissions of fuel were considered, and the boundary was extended to includedelivery transport for resources (human and materials). Emission sources were petrol and diesel.

9.2. Data Collection - Aggregate-Only ProcessThe data is based on information provided by Ecoflex and its suppliers, specifications and qualifiedestimates. Ecoflex uses both pavement methods as part of their civil construction business. The datawas based on on Hunter region projects, however duration data was based on Ecoflex’s nationwideproject averages over the past 16 years used by Ecoflex for calculating project quotations forpotential clients.

Actual data for excavator, E-Pave delivery and aggregate delivery was provided through supplierservice reports.

A supplier statement was used to support vehicle carrying capacity data.

Data from specifications was used for roller, site supervision and back up fuelling utility vehicles.

Duration data estimates for the Aggregate-Only process are based on Ecoflex’s nationwide projectaverage laying rate over the past 16 years (unit per person per hour rate) used for calculating projectquotations for potential clients. These estimates were substantiated by Edser Plant & Civil P/L, anindependent roadworks and earthworks specialist, and again, it was shown that the data providedby Ecoflex was very conservative. Importantly, users of this LCA study should be aware that if theyare comparing E-Pave to an Aggregate-Only pavement requiring ‘Boxing Out’ or preparatoryearthworks, this would significantly increase the emissions profile of the Aggregate-Only pavement,beyond what is calculated here, due to fuel use in both excavation and transport of waste, as well asany resultant waste emissions.

Pavement depths and compaction roller running times are as per engineer specifications for thedesigned subgrade conditions having a California Bearing Ratio (CBR) of 1-2 (nominal).



Factors supplied by Ecoflex, such as scaling factors, were used to allow for ground or site conditionsand were applied equally to calculations of both pavement methods.

Data sources and calculation methodology are detailed in Appendix D.

9.3. Emission Calculations, Emission Factors and Methodologies –Aggregate-Only Process

Table 6 summarises the Aggregate Only Process Life Cycle Inventory. Activity data quantifies the fuelconsumption. Energy content and emissions factors and emission calculation methodology weresourced from National Greenhouse Account (NGA) Factors July 2012. For heavy vehicles, the factorsfor Euro i was used for both pavement methods (to be more conservative). Appendix C sets out thedata components (in grey) used in fuel calculations.

The total petrol consumption was 140 litres.

The total diesel consumption was 36,947 litres.

The column heading “t CO2-e” sets out the emissions quantified from each process and itspercentage in the total inventory.

The total emissions generated by the Aggregate Only Pavement process were 108 tonnes CO2-e.

As with the E-Pave Process Life Cycle Inventory, the emissions were calculated using the formula inFigure 10: Formula for Calculating Fuel-Associated Emissions (source: NGA Factors 2012).

Figure 10: Formula for Calculating Fuel-Associated Emissions


Table 6: Life Cycle Inventory for the Aggregate-Only Process



Energycontentfactor


CO2-e

% ofFoot-print

Site Visit Petrol

Daily Site Visits- Engineering / Supervision-

Crew Cab Utility- Holden Rodeo Petrol (Post 2004

Vehicle)



34.2 GJ/kL 66.92 kg CO2-e/GJ 140 L 0.32 0.30 %

Delivery Transport DieselINFILL

(2:1 Batter angle- engineer specified) Extending base

0.5m on either side-


Service Report &

Tare weights of

trucks statement



38.6 GJ/kL 69.9 kg CO2-e/GJ 31,133.1 L 84.00 78.08 %

CAPPING-


Service Report &

Tare weights of

trucks statement



38.6 GJ/kL 69.9 kg CO2-e/GJ 3,113.31 L 8.4 7.81 %

Preparation and Laying DieselExcavator - Doosan 15 tonne M/C (Euro i) Service Report &

Tare weights of

trucks statement



38.6 GJ/kL 69.9 kg CO2-e/GJ 1,375.00 L 3.71 3.45 %

Back Up Vehicle (Post 2004 Utility) Specification NGERS Method 1 from NGA


38.6 GJ/kL 69.9 kg CO2-e/GJ 933.33 L 2.52 2.34 %

Pavement Laying Labour Transport-Crew Cab Utility-




38.6 GJ/kL 69.9 kg CO2-e/GJ 175 L 0.47 0.44 %

Capping & Edging Labour Transport-Crew Cab Utility-




38.6 GJ/kL 69.9 kg CO2-e/GJ 88 L 0.24 0.22 %

Compaction DieselCS563E Vibrating Smooth Drum (Euro i Vehicle- Low

fuel usage)



38.6 GJ/kL 69.9 kg CO2-e/GJ 130 L 0.35 0.33 %




Energycontentfactor


CO2-e

% ofFoot-print

Embodied emissions for fuelsPetrol extraction, production, transport NGERS Method. NGA Factors

2012, Table 39, p. 71

34.2 GJ/kL 5.3 kg CO2-e/GJ 140 L 0.03 0.02 %

Diesel extraction, production, transport NGERS Method. NGA Factors

2012, Table 39, p. 71

38.6 GJ/kL 5.3 kg CO2-e/GJ 36,947.24 L 7.56 7.03 %

Total emissions 107.59 100%

Figure 11: Emissions Breakdown by Activity – Aggregate-Only Process



9.4. Assumptions / Limitations - Aggregate-Only ProcessThe following table lists the assumptions and limitations of the Aggregate-Only Process:

Table 7: Assumptions / Limitations for the Aggregate-Only Process

Emissions source / activity Assumption / limitation and justification

Site Visit and Preparatory Laying Project Days/Hours calculated based on time required for 3labourers laying 6 m2/hour/person to complete the 5000 m2.This has been substantiated (refer to section 8.2)

Preparatory Laying Hours calculated assumes concurrent use of vehiclesDelivery Transport Location of Quarry to Site: 25 kmSite Visit and Preparatory Laying Location of Office to Site: 20 kmDelivery Transport-Aggregate Quantities for Infill andCapping

Ecoflex applies a 10% scaling factor in the Infill and CappingCalculation for BOTH processes- to allow for extra aggregatedue to irregular ground contour, natural compaction andbatter angle. This results in a factor of 1.12

Delivery Transport All Heavy Vehicle Trucks are non-articulated and Euro i, tobe conservative.

Site Visit and Preparatory Laying Cab crew utility fuel consumption was estimated usingvehicle specifications. Ecoflex applies an additional 20% toallow for site conditions.

2 Refer Appendix C



9.5. Emission Exclusions from Within the System Boundary – Aggregate-Only Process

Geotextile transport emissions have been excluded as they are insignificant and hard to substantiate.Geotextile is delivered to the site, not as an exclusive run, but as part of a large interstate run tomultiple sites, which vary greatly depending on their daily delivery list. As geotextile is required to bedelivered for each method, it was agreed to exclude geotextile transport emissions to reduce theuncertainty of the final calculation.

The following table details why some emissions sources were considered, but ultimately excludedfrom the inventory.

Table 8: Exclusions for Aggregate-Only Process

Emissions source Reason for exclusion and overall implications for footprint

Extraction of rocks (aggregate) Outside system boundary for Gate-to-Gate LCACrushing of rocks (aggregate) Outside system boundary for Gate-to-Gate LCARoad maintenance emissions Outside system boundary for Gate-to-Gate LCAEnd-of-life of access road Outside system boundary for Gate-to-Gate LCAGeotextile Transport Emissions Immaterial and the same amount of carbon emissions

across the two different paving methods.Geotextile Embodied Emissions Outside system boundary for Gate-to-Gate LCA



9.6. Emissions per Functional Unit - Aggregate-Only ProcessThe following table lists the emissions per the functional unit for the Aggregate-Only process:

Table 9: Emissions per Functional Unit – Aggregate-Only Process

Amount of product produced (in functional units) Emissions per functional unit

5000m2 (access road) pavement, Aggregate-Only process 108 tonnes CO2-e

9.7. Assessment of Uncertainty - Aggregate-Only ProcessThe assessment of uncertainty follows the GHG Protocol for the ‘Measurement and EstimationUncertainty of GHG Emissions’ and includes the statistical uncertainties associated with the followingparameters:

1. The energy content factor of the fuel2. The carbon dioxide emission factor of the fuel3. The methane emission factor of the fuel4. The nitrous oxide emission factor of the fuel5. The quantity of fuel combusted

The uncertainties from the energy content factor, the carbon dioxide emission factor, the methaneemission factor and the nitrous oxide emission factor have been taken from the NGER MeasurementDetermination 2008, chapter 8 “Assessment of Uncertainty”.

The uncertainties for the quantity of fuel (+/-5%) combusted have been assessed by Jim Grant,Ecoflex.

Across the direct emissions, the cumulative uncertainty is ‘good’ at +/- 7.5%.



10. Impact Assessment

For this study, we follow the Australian Impact Method which translates emissions, resourceextraction, production and transport into defined indicators.

The only relevant indicator here is the Global Warming Indicator (t CO2-e). This represents climatechange effects resulting from the emissions of greenhouse gases into the atmosphere. The impactsof carbon dioxide, methane and nitrous oxide emissions from both pavement processes are implicitin the 2012 NGA Factors used to calculate the LCA. These conform to Kyoto Protocol (IPCC 1996),based on 100 year time frame and are used in all official reporting.



11. Comparing the Carbon Footprint of E-Pave against theAggregate-Only Process

Having described and quantified the Extended Gate to Gate life cycle inventory of each process, weproceed to analyse the results and present them graphically comparing them for:

Diesel consumptionPetrol consumptionCarbon (greenhouse gas) emissions

Figure 12: Diesel Consumption in Litres Aggregate-Only Versus E-Pave

Diesel consumption is 3.6 times greater using the Aggregate-Only Pavement Process.

Figure 13: Petrol Consumption in Litres Aggregate-Only Versus E-Pave

Petrol consumption is twice as high using the Aggregate-Only Pavement Process.



Carbon emissions generated are 3.6 times greater using the Aggregate-Only Pavement Process.

Figure 14: Carbon Emissions Aggregate-Only Versus E-Pave Figure 15: Carbon Emissions– Pie Chart

All three elements are summarised in the following graph.

Figure 16: E-Pave versus Aggregate-Only; Diesel, Petrol and Carbon Emissions in Percentages



Delivery transport emissions form the highest proportion of both pavement methods by far. Theyamount to 24 tonnes CO2-e in the E-Pave process, representing 81% of the total inventory. For theAggregate-Only process they generate 92.4 tonnes CO2-e of emissions, which is 86% of the totalinventory.

Figure 17: Comparative Carbon Footprint Makeup - E-Pave and Aggregate-Only Methods

Delivery transport emissions are 3.85 times higher in the Aggregate-Only process due to thesignificantly greater amount of aggregate or rock spalls (13,860 tonnes) required to satisfy theengineer specified 2:1 batter angle which extends the base 2 metres either side of the pavementwith a rock spall pavement depth of 1 metre. This compares to a much lower requirement of 2,722.5tonnes of aggregate (rock spalls) for the E-Pave method, extending the base 0.5 m either side, and aninfill pavement depth of 250 mm (the width of a truck tyre E-Pave T-Unit). See Appendix B and C.

If we were to exclude delivery transport emissions altogether, the Aggregate-Only process emissionswould amount to 15.2 tonnes CO2-e. This is still nearly 3 times higher than that for E- Pave (5.6tonnes).



12. Conclusion and Implications

This report details the results, methods, assumptions, boundary and uncertainties of an ExtendedGate to Gate Process LCA for the application of a 5000 m2 (access road) pavement with an engineerspecified 2:1 batter angle:

Ecoflex E-Pave T-units with Aggregate; andAggregate-Only

A painstaking effort was made to source primary data where possible to increase the rigour of thestudy and achieve the goal to communicate credible, independently verified information to informdecisions of stakeholders, both internally and externally. Any qualified estimates made weresubstantiated and conservative.

Figure 18: Comparative Fuel Consumption and Carbon Emissions Performance E-Pave and Aggregate-Only

The processes studied in this ‘Extended Gate to Gate’ LCA include only two components out of theentire life cycle: ‘pavement process’ and ‘raw material delivery transport’ emissions. This includedground preparation, geotextile laying, pavement laying, pavement capping and edge treatment,oversight and compaction emissions. The ‘Gate to Gate’ boundary was extended to include thetransport of raw materials.

The functional unit in this study is the application of 5000 m2 (1000m (L) x 5m (W)) of pavement(access road). Carbon emissions were quantified in a life cycle inventory for each method. Anuncertainty analysis was performed for emissions factors, energy content and activity data. Emissionsources were petrol and diesel. The embodied emissions in petrol and diesel were considered in thisstudy.

The study concludes that the Aggregate-Only method is significantly more fuel and emissions-intensive (360%) than the Ecoflex E-Pave (recycled tyre) approach, primarily due to the amount ofaggregate required to achieve the engineer specified 2:1 batter angle.



The implications of these findings are the significant savings opportunity in emissions (72%), and indiesel (73%) that exist by using E-Pave instead of the conventional Aggregate-Only pavementmethod. This study can be used to inform business cases for strategic and procurement decisions forcivil projects which include laying of access or district roads. In addition, E-Pave has the followingenvironmental and social benefits of:

Use of a resource stream currently being discarded as waste;New job, skill and market creation;Reduced road maintenance;Diversion from landfill;Increased consumer awareness on product stewardship;Catalyst for further innovation.

We have not discussed these benefits here, but they may also form considerations, in conjunctionwith the previously mentioned significant improvements in energy efficiency and greenhouse gasperformance achieved through the E-Pave (access road) pavement method.

The following picture summarises the findings of this extended gate-to-gate comparative LCA.

Figure 19: Carbon Emissions in Tonnes; Aggregate-Only Versus E-Pave Process – Bar Chart



13. Recommendations for Future Improvement of this LCAStudy

1. It is strongly recommended to extend the LCA for the entire life cycle (cradle to grave) to includeembedded emissions from raw material extraction for aggregate, geofabric and the E-Pave Units,as well as investigate road maintenance and end of life treatment for pavements.

From the cradle end, E-Pave manufacture is fairly energy efficient in comparison to quarrying andcrushing of aggregates. (It is common practice for recycled products to begin at the point ofreceipt of the discarded product.)

From the grave end, it is understood that E-Pave roads require little to no maintenance becausethe infill is free draining and does not retain water or create pot holes, and the E-Pave maintainsthe strength and integrity of the road over time. It would make an interesting comparison toAggregate-Only roads.

Thus, it can be seen that a cradle to grave LCA provides further opportunities to highlight thedifferences in emissions intensity of the two pavement methods.

2. More comparative study into other alternative uses for recycled tyres and their relative meritsand implications to the LCA.



14. Appendix A: Additional Considerations - Rising InputCosts and Carbon Pricing

In the recent announcement by Boral of a Quarries Price increase to be introduced 1 April 2013, theprice of aggregates will be increasing by $3 - $5.00 per tonne. At the same time, resource recovery inthe form of tyre recycling is being incentivised. Indirectly, this is occurring through carbon pricing ofnon-legacy landfill waste, introduced 1 July 2012, increasing the cost of used tyre disposal. Directly, itis occurring through the current development of the Tyre Stewardship Scheme by industry andGovernment.

In addition, fuel prices are increasing due the carbon price (less fuel tax credits), which will putfurther pressure on diesel prices.

These trends provide a timely reminder that the results of this study will be further impacted infavour of the cost efficient E-Pave approach in this new context of sharply rising input costs. Thisindicates that the more fuel and emissions intensive Aggregate-Only method will becomeincreasingly more expensive and commercially less attractive in a cost and carbon constrainedeconomy. It is much more sensitive to increases in prices, such as fuel, oil (impacts polypropylenegeofabric costs), aggregate and carbon, placing pressures on liable entities. Australian companiesthat are increasingly conscious of the implications of ‘cost pass through’ along the supply chain, arealso aware of the need to understand carbon emission profiles, such as those in this study, and touse that knowledge as part of their own business risk and emission reduction strategies.



15. Appendix B –Data Set E-Pave Process Lifecycle Inventory

Table 10: Data Set E-Pave Process Lifecycle Inventory



16. Appendix C –Data Set Aggregate-Only Process Lifecycle Inventory

Figure 20: Data Set Aggregate-Only Process Lifecycle Inventory



17. Appendix D – Data Set Substantiation References

Table 11: Data Substantiation – Both Processes



Figure 21: Data Substantiation Engineer Specification – Letter



Figure 22: Data Substantiation Engineer Specification - Calculations



Figure 23: Data Substantiation Engineer Specification - Drawings



Sustainable Business Consulting is an Australian industry leaderin sustainability, carbon & energy consulting and training. Weare driven by quality and take pride in a job well done.For more information please contact: Barbara Albert, ManagingDirector, at [email protected]

Sustainable Business Consulting Pty Ltd | Level 32, 101 Miller Street, North Sydney 2060P: 1300 102 195 | F: +61 2 8079 6101 | www.sustainablebizconsulting.com.au

ACN 140 233 932 | ABN 46 506 219 241

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